The oncologist, writer and performer Rob Buckman, who has died aged 63 in his sleep on board a plane, spent last week making a series of short films. We were working on them together, and Rob was his usual irrepressible self, full of good humour, jokes and kindness. On Sunday the whole film crew had lunch in a pub, and Rob left to catch the flight to Toronto on which he died. The films, ironically, are called Top Ten Tips for Health.

The Guardian writer Nancy Banks-Smith described Rob as "one of those exciting scientists in full fizz who look as if they have access to a strong tonic not yet on the market". She was reviewing a film he made in 1981 called Your Own Worst Enemy. He was then suffering from an autoimmune disease called dermatomyositis, in which the body's defences start to attack the body itself. At the time he started filming, Rob assumed the disease would prove fatal, and had determined to make the film to educate people on the subject. But one last treatment of blood plasma replacement and a new drug stopped the disease. However, he later suffered from another autoimmune disease that left him semi-paralysed. Banks-Smith remarked on his courage and fortitude: "The surviving drive to describe his own disease and dissolution was one of the most striking scientific achievements I have seen on television."

Rob was born in London to Bernard Buckman, a trader, and his wife, Irene, a barrister. He began his acting career at the age of 13, while still at University College school, north London, playing the Midshipmite in Gilbert and Sullivan's HMS Pinafore at the Savoy theatre. Then he went on to St John's College, Cambridge, where he graduated in medicine in 1972, after having featured in a vintage Footlights team.

As a junior doctor at University College hospital, London, he met Chris Beetles, and they teamed up as Beetles and Buckman to perform live comedy and revue. Rob wrote for the long-running satirical BBC Radio 4 show Week Ending, and for an LWT sitcom, Doctor On the Go, based on Richard Gordon's Doctor in the House books.

Beetles and Buckman then performed their own material in another LWT series, The Pink Medicine Show (1978). I first encountered them at the Amnesty International fundraiser The Secret Policeman's Ball in 1979, and Rob went on to front a long-running ITV medical series in the 1980s with Miriam Stoppard, Where There's Life.

Unable to find a consultant's job in oncology in the UK, Rob emigrated to Canada in 1985 and took up a post at the Sunnybrook hospital in Toronto. But he carried on making television programmes. In Magic or Medicine? (1994), he investigated alternative therapies, while Human Wildlife: The Life That Lives On Us (2002) looked at microbes in the home environment.

Besides contributing to Punch and writing a weekly column for the Toronto Globe and Mail, Rob also wrote many books, including Jogging from Memory: Letters to Sigmund Freud (1980); How to Break Bad News: A Guide for Healthcare Professionals (1992); Not Dead Yet: The Unauthorized Autobiography of Dr Robert Buckman, Complete With Map, Many Photographs and Irritating Footnotes (1999); Cancer is a Word, Not a Sentence (2006); and Can We Be Good Without God?: Biology, Behaviour and the Need to Believe (2002).

He was president of the Humanist Association of Canada; chair of the advisory board on bioethics of the International Humanist and Ethical Union; and a fellow of the Royal College of Physicians in the UK, and of its Canadian counterpart. He became a pioneer of communication and supportive care in medicine at the Princess Margaret Hospital in Toronto, and was professor in the department of medicine at the University of Toronto.

Despite his physical problems, Rob was the most positive and energetic person I have met. He was constantly in good spirits, able to fill a room with warmth and laughter, and never short of ideas and projects. He was also a fount of kindness – always thinking about other people and never about his own problems.

With his first wife, Joan van den Ende, he had two daughters, Joanna and Susie, and with his second, Pat Shaw, two sons, James and Matthew. All of them survive him.

Russell Davies writes: The long and serious careers of Rob Buckman would have been hard to predict in the late 1960s, when he was an irrepressible, rubber-legged star of the Cambridge Footlights Revue. True, he took an unsparing view of medical matters even then – in one of his sketches, the television series on surgery Your Life in Their Hands re-emerged as Their Knife in Your Glands – but he was better known for the capering glee he communicated on stage. I shared many routines with him, most of them directed by Clive James: a pseudo-Russian dance ensemble; a slow-motion wrestling sketch that was taken up, bizarrely, by the BBC for The Val Doonican Show; and Rob's curiously rhapsodic, but not very rude, striptease number.

This was mostly physical stuff but verbally he was also very sharp. We worked up a piece called Chippenham Wrexham, in which two chefs intertwiningly recited a long but quick-fire recipe, incorporating as many British place-names as would fit the theme of cookery. It was a beast to perform, but I never knew him to flub a word of it. He was always more energetic than the rest of us put together, and his later illnesses caused us – who knew nothing of medicine – to wonder if it is possible to have too much vitality. We shall always remember him grinning – and making us grin.

• Robert Alexander Amiel Buckman, doctor, writer and broadcaster, born 22 August 1948; died 9 October 2011